Particulate matter, from incineration

Miller and co-workers show an on-stream sampler and a portable GC system to analyze stack gases as part of the requirements of determination of particulate matter from incinerator stacks. The concentrations of carbon dioxide, oxygen, and carbon monoxide are measured and that of nitrogen is calculated by difference. This method is of higher precision and can save time and labor when compared with the Orsat analyzer method. Further, this GC system is portable and all the components are mounted on a 2 ft by 3 ft laboratory cart, which makes mobile measurements possible. A summary of some of the techniques used is presented in Table 6.2. 

Spark arrestors are provided on the exhaust of source or fire where a hot particulate might be released (i.e., internal combustion engines, chimneys, incinerator stacks, etc ). The spark arrestor consist of a fine metal screen to prevent the particulate matter from being released from the exhaust mechanism. 

For the convenience of the operator, waste should be packaged in uniform-sized packages designed for ease of handling. Asphalt-lined bags should be avoided because of the evolution of excessive particulate matter from their incineration. Fiberboard cartons or drums are generally satisfactory. 

Temperature. The temperature for combustion processes must be balanced between the minimum temperature required to combust the original contaminants and any intermediate by-products completely and the maximum temperature at which the ash becomes molten. Typical operating temperatures for thermal processes are incineration (750—1650°C), catalytic incineration (315—550°C), pyrolysis (475—815°C), and wet air oxidation (150—260°C at 10,350 kPa) (15). Pyrolysis is thermal decomposition in the absence of oxygen or with less than the stoichiometric amount of oxygen required. Because exhaust gases from pyrolytic operations are somewhat "dirty" with particulate matter and organics, pyrolysis is not often used for hazardous wastes. 

Optimized modern dry scrubbing systems for incinerator gas cleaning are much more effective (and expensive) than their counterparts used so far for utility boiler flue gas cleaning. Brinckman and Maresca [ASME Med. Waste Symp. (1992)] describe the use of dry hydrated lime or sodium bicarbonate injection followed by membrane filtration as preferred treatment technology for control of acid gas and particulate matter emissions from modular medical waste incinerators, which have especially high dioxin emissions. 

SW-846, is used to measure emissions of semivolatile principal organic constituents. Method 0010 is designed to determine destruction and removal efficiency (DRE) of POHCs from incineration systems. The method involves a modification of the EPA Method 5 sampling train and may be used to determine particulate emission rates from stationary sources. The method is applied to semivolatile compounds, including polychlorinated biphenyls (PCBs), chlorinated dibenzodioxins and dibenzofurans, polycyclic organic matter, and other semivolatile organic compounds. 

Significant dispersion of hexachlorobutadiene has been confirmed by the detection of hexachlorobutadiene at areas which are far removed from release sources (Class and Ballschmiter 1987). A high partition coefficient (log Ko=) value of 3.67 (Montgomery and Welkom 1990) for hexachlorobutadiene indicates that adsorption to soils with high organic carbon content can occur. Wind erosion of contaminated surface soils can then lead to airborne hexachlorobutadiene-containing particulate matter. Levels of hexachlorobutadiene have been detected in fly ash from the incineration of hexachlorobutadiene-containing hazardous waste (Junk... 

Source Tracers. The principal anthropogenic sources of primary suspended particulate matter in New York City are transportation, fuel, oil combustion for power and space heating, and incineration (, 15). From approximately November through... 

In developing a multiple regression model for apportioning sources of TSP in New York City, Kleinman, et al.(2) selected Pb, Mn, Cu, V and SO, as tracers for automotive sources, soil-related sources, incineration, oil-burning and secondary particulate matter, respectively. These were chosen on the basis of the results of factor analysis and a qualitative knowledge of the principal types of sources in New York City and the trace metals present in emissions from these types of sources. Secondary TSP, automotive sources and soil resuspension were found to be the principal sources of TSP in 1974 and 1975 ( ). 

In the pure form, CDDs are colorless solids or crystals. CDDs enter the environment as mixtures containing a variety of individual components and impurities. In the environment they tend to be associated with ash, soil, or any surface with a high organic content, such as plant leaves. In air and water, a portion of the CDDs may be found in the vapor or dissolved state, depending on the amount of particulate matter, temperature, and other environmental factors. 2,3,7,8-TCDD is odorless. The odors of the other CDDs are not known. CDDs are known to occur naturally, and are also produced by human activities. They are naturally produced from the incomplete combustion of organic material by forest fires or volcanic activity. CDDs are not intentionally manufactured by industry, except in small amounts for research purposes. They are unintentionally produced by industrial, municipal, and domestic incineration and combustion processes. Currently, it is believed that CDD emissions associated with human incineration and combustion activities are the predominant environmental source. 

To improve energy efficiency, refractories with superior K factors are used in lining the kiln, thus reducing radiant heat losses. Moreover, kiln mounted blowers now inject combustion air into the kilns in the zone where the volatiles evolve from the coke, thus permitting utilization of the Btu content in these previously wasted gases. In modern calciners, most of the energy required is obtained by burning the coke volatiles and fine particulate matter in the kiln. In some instances, rotary kilns equipped with kiln mounted blowers actually operate without external fuel (except for start-up). When these units are also equipped with incinerators (to combust the unburned volatiles and emitted coke fines) and waste... 

The presence of heavy metals in the atmospheric particulate matter in Antarctica can be attributed to different sources, both natural and anthropogenic. Some authors state that almost all natural sources of heavy metals in Antarctica are generally situated in the southern hemisphere (4, 14, 15). The natural sources are normally volcanic activities, erosive processes, continental dusts, marine spray from the ocean, low-temperature biological processes, etc. (7, 10, 16-18). Important local human sources of heavy metal emissions into the Antarctic atmosphere are presumed to be the Antarctic stations and their activities, especially all kinds of transport, power plants, waste burning (incinerators), etc. (10, 12, 15, 19). 

Particulate Matter and Heavy Metal Emissions from Incinerators... 

Chemical Processes for Particulate Matter Formation Most chemical processes that produce particulates are combustion processes, as we have mentioned already. These processes include fossil fuel fired power plants, incinerators, home furnaces, fireplaces and stoves, cement kilns, internal combustion engines, forest, brush and grass fires, and active volcanoes. Particles from combustion sources tend to occur in a size < 1 fjtm. Such small particulates are particularly important because they are readily carried into the alveoli of lungs and are relatively enriched in more hazardous constituents, such as toxic heavy metals and arsenic. 

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